[U-Boot] [PATCH 07/32] nitrogen6x: Allow U-Boot to be silent on UART2

[Stefano Babic]

Hi Eric,

On 02/10/2014 21:16, Eric Nelson wrote:
> Several customers are using UART2 (normally the serial console
> for U-Boot) as connections to printers or other peripherals
> that are not tolerant of stray inputs during reset.
> 
> Provide a simple way to eliminate output on the serial port
> by conditionally configuring these pads as GPIOs during
> U-Boot.
> 
> Signed-off-by: Eric Nelson <eric.nelson at boundarydevices.com>
> ---
>  board/boundary/nitrogen6x/nitrogen6x.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/board/boundary/nitrogen6x/nitrogen6x.c b/board/boundary/nitrogen6x/nitrogen6x.c
> index e795492..621cdbc 100644
> --- a/board/boundary/nitrogen6x/nitrogen6x.c
> +++ b/board/boundary/nitrogen6x/nitrogen6x.c
> @@ -77,9 +77,15 @@ static iomux_v3_cfg_t const uart1_pads[] = {
>  	MX6_PAD_SD3_DAT7__UART1_TX_DATA | MUX_PAD_CTRL(UART_PAD_CTRL),
>  };
>  
> +/* #define CONFIG_SILENT_UART */

Theoretically, we have already in U-Boot CONFIG_SILENT_CONSOLE, without
the need to introduce a new CONFIG_.

>  static iomux_v3_cfg_t const uart2_pads[] = {
> +#ifndef CONFIG_SILENT_UART
>  	MX6_PAD_EIM_D26__UART2_TX_DATA | MUX_PAD_CTRL(UART_PAD_CTRL),
>  	MX6_PAD_EIM_D27__UART2_RX_DATA | MUX_PAD_CTRL(UART_PAD_CTRL),
> +#else
> +	MX6_PAD_EIM_D26__GPIO3_IO26 | MUX_PAD_CTRL(UART_PAD_CTRL),
> +	MX6_PAD_EIM_D27__GPIO3_IO27 | MUX_PAD_CTRL(UART_PAD_CTRL),
> +#endif

I understand the reason, anyway this looks like a hack (uart is still
configured while iomux is not correctly set). Can you check if your goal
is simply reached with CONFIG_SILENT_CONSOLE ?

Best regards,
Stefano Babic


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